Invented in 1743 in its current form by Benjamin Franklin, the Glass Harmonica is a nested row of glass hemispheres played (like wineglasses) with a moistened finger. All the pieces here were written for the instrument by Beethoven, Mozart, Donizetti, Apell, Block, Sombach, Naumann, Reichardt, Rollig, Schulz, spanning 1750-1962. A good opportunity to hear what the instrument can do. And cheap.